diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 9439680..9a05fe3 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -8,9 +8,9 @@ jobs:
   builddist:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
-    - uses: actions/setup-python@v4
+    - uses: actions/setup-python@v5
       with:
         python-version: 3.x
 
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 873e065..f6b8c84 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -24,9 +24,9 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python 3.x
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: 3.x
     - name: Windows Venv
@@ -58,9 +58,9 @@ jobs:
       matrix:
         python-version: [ "pypy-3.10", "3.8", "3.9", "3.10", "3.11"]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Setup Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install
@@ -89,9 +89,9 @@ jobs:
     needs: versions
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Setup Python
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: "3.10"
     - name: Install phmutest
@@ -107,12 +107,9 @@ jobs:
         isort -
     - name: Formatting
       # Show reformatting changes.
-      # Make the changes.
-      # Subsequent steps run with the modified files.
       # Don't run black on the generated test files.
       run: |
-        black **/*.py --check --force-exclude="tests/py"
-        black **/*.py --force-exclude="tests/py"
+        black **/*.py --diff --force-exclude="tests/py"
       continue-on-error: true
     - name: Code Style
       run: |
@@ -130,7 +127,7 @@ jobs:
         python docs/premkdocs.py
         mkdocs build
     - name: Upload mkdocs site
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: site
         path: site
@@ -141,10 +138,10 @@ jobs:
     needs: inspect
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python 3.x
       id: setuppython
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: 3.x
     - name: Install phmutest
@@ -167,7 +164,7 @@ jobs:
       continue-on-error: true
 
     - name: Upload coverage reports to Codecov
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v4
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
         files: ./coverage.xml # optional
diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index 11c4f96..80b63ca 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -14,10 +14,10 @@ jobs:
   coverage:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python 3.x
       id: setuppython
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: 3.x
     - name: Install phmutest
@@ -40,7 +40,7 @@ jobs:
       continue-on-error: true
 
     - name: Upload coverage reports to Codecov
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v4
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
         files: ./coverage.xml # optional
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 7398923..5030336 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -6,17 +6,17 @@ on:
   workflow_dispatch:
 
 env:
-  ref: v0.0.3
+  ref: v0.0.4
 
 jobs:
   builddist:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
       with:
         ref: ${{ env.ref }}
 
-    - uses: actions/setup-python@v4
+    - uses: actions/setup-python@v5
       with:
         python-version: 3.x
 
@@ -27,7 +27,7 @@ jobs:
         python -m pip hash dist/*
 
     - name: Upload dist
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: dist-${{ env.ref }}
         path: dist/*
diff --git a/.github/workflows/wheel.yml b/.github/workflows/wheel.yml
index a9d0df3..b5bee84 100644
--- a/.github/workflows/wheel.yml
+++ b/.github/workflows/wheel.yml
@@ -5,14 +5,14 @@ on:
 
 env:
   project: phmutest
-  version: 0.0.3
+  version: 0.0.4
   command: phmutest
 
 jobs:
   pypi-install:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/setup-python@v4
+    - uses: actions/setup-python@v5
       with:
         python-version: "3.10"
 
diff --git a/LICENSE b/LICENSE
index 917f8a8..1d862c7 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023 Mark Taylor
+Copyright (c) 2024 Mark Taylor
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index ba819b0..dba8787 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# phmutest 0.0.3
+# phmutest 0.0.4
 
 ## Detect broken Python examples in Markdown
 
diff --git a/docs/api.md b/docs/api.md
index b5b78e5..eaebf9e 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -1,4 +1,4 @@
-# Tool API for phmutest version 0.0.3
+# Tool API for phmutest version 0.0.4
 
 ## API - phmutest.tool
 
diff --git a/docs/fixture_py.md b/docs/fixture_py.md
index 0092004..fa18bf9 100644
--- a/docs/fixture_py.md
+++ b/docs/fixture_py.md
@@ -1,7 +1,7 @@
 # src/phmutest/fixture.py
 
 ```python
-"""v0.0.3 Keyword arguments passed to --fixture function and return type Fixture.
+"""v0.0.4 Keyword arguments passed to --fixture function and return type Fixture.
 
 These are passed to the fixture function as keyword arguments:
 
@@ -21,6 +21,7 @@ is_replmode
     Python bool. True when commandline argument --replmode is present.
 
 """
+
 from dataclasses import dataclass
 from typing import Callable, MutableMapping, Optional
 
diff --git a/docs/generated_project_py.md b/docs/generated_project_py.md
index 012d988..514299e 100644
--- a/docs/generated_project_py.md
+++ b/docs/generated_project_py.md
@@ -10,6 +10,7 @@ from phmutest.skip import sys_tool as _phm_sys
 
 _phm_globals = None
 _phm_testcase = unittest.TestCase()
+_phm_testcase.maxDiff = None
 _phm_log = []
 
 
diff --git a/docs/generated_share_demo_py.md b/docs/generated_share_demo_py.md
index 61c759d..86ab165 100644
--- a/docs/generated_share_demo_py.md
+++ b/docs/generated_share_demo_py.md
@@ -10,6 +10,7 @@ from phmutest.skip import sys_tool as _phm_sys
 
 _phm_globals = None
 _phm_testcase = unittest.TestCase()
+_phm_testcase.maxDiff = None
 _phm_log = []
 
 
diff --git a/docs/make_wrapped_examples.py b/docs/make_wrapped_examples.py
index 1793e6d..e58e842 100644
--- a/docs/make_wrapped_examples.py
+++ b/docs/make_wrapped_examples.py
@@ -1,4 +1,5 @@
 """Create Markdown wrappers around the project's example .py files."""
+
 from pathlib import Path
 
 top = "# <put filename here>\n\n```python\n"
diff --git a/docs/premkdocs.py b/docs/premkdocs.py
index 4fc9e65..833f198 100644
--- a/docs/premkdocs.py
+++ b/docs/premkdocs.py
@@ -6,6 +6,7 @@
 - enter Ctrl-C to discontinue watching and shut down the mkdocs server
 Suggest adding the mkdocs.yml docs_dir to .gitignore.
 """
+
 import subprocess
 import sys
 from multiprocessing import Process
diff --git a/docs/recent_changes.md b/docs/recent_changes.md
index 53f39dd..7be0f7d 100644
--- a/docs/recent_changes.md
+++ b/docs/recent_changes.md
@@ -22,3 +22,9 @@
 0.0.3 - 2023-09-24
 
 - Add test_importer.py. Cleanups
+
+0.0.4 - 2024-09-05
+
+- Bugfix- Issue- The generated expected output check in code mode
+  asserts if the FCB length is greater than a fairly small value.
+- Python source formatting updates per Black 24.3.0.
diff --git a/mkdocs.yml b/mkdocs.yml
index 3423ad9..3173c65 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -1,6 +1,6 @@
-site_name: phmutest 0.0.3
+site_name: phmutest 0.0.4
 site_description: Detect broken Python examples in Markdown
-copyright: Copyright (c) 2023 Mark Taylor
+copyright: Copyright (c) 2024 Mark Taylor
 docs_dir: _mkdocsin
 theme: readthedocs
 nav:
diff --git a/setup.cfg b/setup.cfg
index 4d8e1c0..2a73056 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -7,7 +7,7 @@ license_files = LICENSE
 
 # https://setuptools.readthedocs.io/en/latest/userguide/declarative_config.html
 name = phmutest
-version = 0.0.3
+version = 0.0.4
 author = Mark Taylor
 author_email = mark66547ta2@gmail.com
 description = Detect broken Python examples in Markdown.
diff --git a/src/phmutest/__init__.py b/src/phmutest/__init__.py
index 27fdca4..81f0fde 100644
--- a/src/phmutest/__init__.py
+++ b/src/phmutest/__init__.py
@@ -1 +1 @@
-__version__ = "0.0.3"
+__version__ = "0.0.4"
diff --git a/src/phmutest/cases.py b/src/phmutest/cases.py
index 2a2b6d3..572bc0b 100644
--- a/src/phmutest/cases.py
+++ b/src/phmutest/cases.py
@@ -1,4 +1,5 @@
 """Generate test cases as a unittest test file."""
+
 import argparse
 from pathlib import Path
 
@@ -75,12 +76,12 @@ def render_setup_module(
     replacements["shareid"] = shareid
     replacements["setupblocks"] = deindented_setup_blocks
     if args.progress:
-        replacements[
-            "showprogressenter"
-        ] = '_phm_sys.stderr_printer("setUpModule()...")'
-        replacements[
-            "showprogressexit"
-        ] = '_phm_sys.stderr_printer("leaving setUpModule.")'
+        replacements["showprogressenter"] = (
+            '_phm_sys.stderr_printer("setUpModule()...")'
+        )
+        replacements["showprogressexit"] = (
+            '_phm_sys.stderr_printer("leaving setUpModule.")'
+        )
 
     if args.fixture:
         replacements["userfixtureglobs"] = phmutest.subtest.justify(
@@ -128,12 +129,12 @@ def render_teardown_module(
     replacements["teardownblocks"] = deindented_teardown_blocks
 
     if args.progress:
-        replacements[
-            "showprogressenter"
-        ] = '_phm_sys.stderr_printer("tearDownModule()...")'
-        replacements[
-            "showprogressexit"
-        ] = '_phm_sys.stderr_printer("leaving tearDownModule.")'
+        replacements["showprogressenter"] = (
+            '_phm_sys.stderr_printer("tearDownModule()...")'
+        )
+        replacements["showprogressexit"] = (
+            '_phm_sys.stderr_printer("leaving tearDownModule.")'
+        )
 
     return phmutest.subtest.fill_in(
         teardown_module_form,
@@ -319,6 +320,7 @@ def markdown_file(
 $callfixture
 _phm_globals = None
 _phm_testcase = unittest.TestCase()
+_phm_testcase.maxDiff = None
 _phm_log = []
 $setupmodule
 $teardownmodule
diff --git a/src/phmutest/code.py b/src/phmutest/code.py
index af50bd7..10c6bc1 100644
--- a/src/phmutest/code.py
+++ b/src/phmutest/code.py
@@ -1,4 +1,5 @@
 """Run the generated unittest source file with unittest.main."""
+
 import argparse
 import copy
 import importlib
diff --git a/src/phmutest/config.py b/src/phmutest/config.py
index f131a50..c369910 100644
--- a/src/phmutest/config.py
+++ b/src/phmutest/config.py
@@ -16,6 +16,7 @@
           --generate, --progress, --sharing,
           --log, --summary, --report
 """
+
 import argparse
 from pathlib import Path
 from typing import List
diff --git a/src/phmutest/direct.py b/src/phmutest/direct.py
index 2e22e37..396eb73 100644
--- a/src/phmutest/direct.py
+++ b/src/phmutest/direct.py
@@ -1,4 +1,5 @@
 """Find phmutest Directives in HTML comment Nodes."""
+
 import re
 from dataclasses import dataclass
 from enum import Enum, auto
diff --git a/src/phmutest/fixture.py b/src/phmutest/fixture.py
index 9cbd055..d0e7c61 100644
--- a/src/phmutest/fixture.py
+++ b/src/phmutest/fixture.py
@@ -1,4 +1,4 @@
-"""v0.0.3 Keyword arguments passed to --fixture function and return type Fixture.
+"""v0.0.4 Keyword arguments passed to --fixture function and return type Fixture.
 
 These are passed to the fixture function as keyword arguments:
 
@@ -18,6 +18,7 @@
     Python bool. True when commandline argument --replmode is present.
 
 """
+
 from dataclasses import dataclass
 from typing import Callable, MutableMapping, Optional
 
diff --git a/src/phmutest/globs.py b/src/phmutest/globs.py
index dbaa34d..fbe9f24 100644
--- a/src/phmutest/globs.py
+++ b/src/phmutest/globs.py
@@ -1,4 +1,5 @@
 """Imported by the generated test file to manage test module globals."""
+
 import inspect
 import sys
 import types
diff --git a/src/phmutest/importer.py b/src/phmutest/importer.py
index 3c2c21c..5f34b18 100644
--- a/src/phmutest/importer.py
+++ b/src/phmutest/importer.py
@@ -1,4 +1,5 @@
 """Import user's fixture function given the relative dotted path."""
+
 import importlib.util
 import sys
 from pathlib import Path
diff --git a/src/phmutest/main.py b/src/phmutest/main.py
index 0935f0f..03a1e34 100644
--- a/src/phmutest/main.py
+++ b/src/phmutest/main.py
@@ -1,4 +1,5 @@
 """Command line parsing, main entry point, and top level operations."""
+
 import argparse
 import pathlib
 import sys
diff --git a/src/phmutest/printer.py b/src/phmutest/printer.py
index 36d8eb2..f7cb4c0 100644
--- a/src/phmutest/printer.py
+++ b/src/phmutest/printer.py
@@ -1,4 +1,5 @@
 """Context manager to print and log entry and exit status of a code block run."""
+
 import contextlib
 import io
 import sys
diff --git a/src/phmutest/select.py b/src/phmutest/select.py
index acb8af8..abc9183 100644
--- a/src/phmutest/select.py
+++ b/src/phmutest/select.py
@@ -1,4 +1,5 @@
 """Identify/select/deselect FCBs per info string, test groups and directives."""
+
 import argparse
 from dataclasses import dataclass
 from pathlib import Path
diff --git a/src/phmutest/session.py b/src/phmutest/session.py
index cd03ef0..25daaf7 100644
--- a/src/phmutest/session.py
+++ b/src/phmutest/session.py
@@ -1,4 +1,5 @@
 """Generate and run docstests for Python interactive session FCBs."""
+
 import argparse
 import doctest
 import itertools
diff --git a/src/phmutest/skip.py b/src/phmutest/skip.py
index 76f42e1..aad1471 100644
--- a/src/phmutest/skip.py
+++ b/src/phmutest/skip.py
@@ -1,4 +1,5 @@
 """Process skip directives. Encapsulate access to Python standard library sys."""
+
 import argparse
 import sys
 from dataclasses import dataclass
@@ -69,9 +70,9 @@ def make_replacements(
     """Create mapping for Template string replacement."""
     replacements = dict(line=doc_location, log_reason=log_reason)
     if verbose:
-        replacements[
-            "print"
-        ] = f'_phm_sys.stderr_printer("{doc_location} ... skip   {log_reason}")'
+        replacements["print"] = (
+            f'_phm_sys.stderr_printer("{doc_location} ... skip   {log_reason}")'
+        )
     return replacements
 
 
diff --git a/src/phmutest/subtest.py b/src/phmutest/subtest.py
index 25ae652..2fbda09 100644
--- a/src/phmutest/subtest.py
+++ b/src/phmutest/subtest.py
@@ -1,4 +1,5 @@
 """Generate code to test Python FCBs."""
+
 import argparse
 import re
 import textwrap
diff --git a/src/phmutest/summary.py b/src/phmutest/summary.py
index 0c07540..46c5b17 100644
--- a/src/phmutest/summary.py
+++ b/src/phmutest/summary.py
@@ -1,4 +1,5 @@
 """Define main() result type. Print test results."""
+
 import argparse
 import unittest
 from collections import Counter
diff --git a/src/phmutest/tool.py b/src/phmutest/tool.py
index b23e8a5..9766540 100644
--- a/src/phmutest/tool.py
+++ b/src/phmutest/tool.py
@@ -1,4 +1,5 @@
 """General purpose tools get fenced code blocks from Markdown."""
+
 from dataclasses import dataclass
 from operator import attrgetter
 from pathlib import Path
diff --git a/tests/check_classifiers.py b/tests/check_classifiers.py
index 9a8541c..cf07277 100644
--- a/tests/check_classifiers.py
+++ b/tests/check_classifiers.py
@@ -10,6 +10,7 @@
 
 https://pypi.org/classifiers/
 """
+
 import configparser
 import sys
 
diff --git a/tests/conftest.py b/tests/conftest.py
index e523864..cb7b80b 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,4 +1,5 @@
 """Fixtures used in multiple test files. Checkers are helpful with pytest 6.2.5."""
+
 import inspect
 import unittest
 
diff --git a/tests/py/generated_project.py b/tests/py/generated_project.py
index 106060a..d13c277 100644
--- a/tests/py/generated_project.py
+++ b/tests/py/generated_project.py
@@ -7,6 +7,7 @@
 
 _phm_globals = None
 _phm_testcase = unittest.TestCase()
+_phm_testcase.maxDiff = None
 _phm_log = []
 
 
diff --git a/tests/py/generated_sharedemo.py b/tests/py/generated_sharedemo.py
index 92e1480..665ab5e 100644
--- a/tests/py/generated_sharedemo.py
+++ b/tests/py/generated_sharedemo.py
@@ -7,6 +7,7 @@
 
 _phm_globals = None
 _phm_testcase = unittest.TestCase()
+_phm_testcase.maxDiff = None
 _phm_log = []
 
 
diff --git a/tests/test_api.py b/tests/test_api.py
index 2b80357..f92b983 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1,4 +1,5 @@
 """Check the hand copying from tool.py into api.md."""
+
 from pathlib import Path
 
 import phmutest.tool
@@ -25,4 +26,4 @@ def test_api():
     # wc src/phmutest/tool.py
     exp_code_length = len(codetext)
     msg = f"tool.py length has changed to {exp_code_length}, is api.md up to date?"
-    assert exp_code_length == 5339, msg
+    assert exp_code_length == 5340, msg
diff --git a/tests/test_cases.py b/tests/test_cases.py
index 2e2cfa3..9432be5 100644
--- a/tests/test_cases.py
+++ b/tests/test_cases.py
@@ -1,4 +1,5 @@
 """Tests for cases.py and other source files to provide code coverage."""
+
 import contextlib
 import io
 import textwrap
diff --git a/tests/test_direct.py b/tests/test_direct.py
index 09b9051..436973b 100644
--- a/tests/test_direct.py
+++ b/tests/test_direct.py
@@ -1,4 +1,5 @@
 """Test HTML comment directives implemented in direct.py and fenced.py."""
+
 from pathlib import Path
 
 import phmutest.select
diff --git a/tests/test_dist.py b/tests/test_dist.py
index c577b2f..b7d772a 100644
--- a/tests/test_dist.py
+++ b/tests/test_dist.py
@@ -1,4 +1,5 @@
 """Test project packaging."""
+
 import configparser
 import subprocess
 from pathlib import Path
@@ -65,7 +66,7 @@ def test_wheel_yml(self):
 
 def test_consistent_copyright():
     """Assure same copyright phrasing in the various source locations."""
-    year = 2023
+    year = 2024
     assert f"Copyright (c) {year}" in Path("LICENSE").read_text(encoding="utf-8")
     assert f"Copyright (c) {year}" in Path("mkdocs.yml").read_text(encoding="utf-8")
 
diff --git a/tests/test_docs.py b/tests/test_docs.py
index f57bb34..02120eb 100644
--- a/tests/test_docs.py
+++ b/tests/test_docs.py
@@ -1,4 +1,5 @@
 """pytest tests for README.md and other Markdown doc files."""
+
 import contextlib
 import re
 import textwrap
diff --git a/tests/test_errors.py b/tests/test_errors.py
index 13a831b..f14802c 100644
--- a/tests/test_errors.py
+++ b/tests/test_errors.py
@@ -1,4 +1,5 @@
 """Check handling of user code raising an exception.  Python code, REPLs, --fixture."""
+
 import contextlib
 import io
 
diff --git a/tests/test_examples.py b/tests/test_examples.py
index 5f14e1c..f30983f 100644
--- a/tests/test_examples.py
+++ b/tests/test_examples.py
@@ -1,4 +1,5 @@
 """Test runs calling phmutest.main.main() from Python with command line arguments."""
+
 import phmutest.main
 import phmutest.summary
 
diff --git a/tests/test_extra_args.py b/tests/test_extra_args.py
index e42c222..cdc3030 100644
--- a/tests/test_extra_args.py
+++ b/tests/test_extra_args.py
@@ -1,4 +1,5 @@
 """Check pass through of extra args to unittest."""
+
 import pytest
 
 import phmutest.main
diff --git a/tests/test_fenced.py b/tests/test_fenced.py
index ce0979e..28f25f6 100644
--- a/tests/test_fenced.py
+++ b/tests/test_fenced.py
@@ -1,4 +1,5 @@
 """Test Python info string matching, command line skip, and --report."""
+
 import phmutest.main
 import phmutest.summary
 
diff --git a/tests/test_generate.py b/tests/test_generate.py
index c045a06..20e0a93 100644
--- a/tests/test_generate.py
+++ b/tests/test_generate.py
@@ -1,4 +1,5 @@
 """Check handling of --generate command line option."""
+
 import os
 import unittest
 import unittest.main
diff --git a/tests/test_globs.py b/tests/test_globs.py
index 70ce93c..907afba 100644
--- a/tests/test_globs.py
+++ b/tests/test_globs.py
@@ -1,4 +1,5 @@
 """Test Globals class from globs.py."""
+
 import copy
 import doctest
 import sys
diff --git a/tests/test_patching.py b/tests/test_patching.py
index 6044b44..f48e7e5 100644
--- a/tests/test_patching.py
+++ b/tests/test_patching.py
@@ -1,4 +1,5 @@
 """Show use cases for patch points."""
+
 import copy
 import doctest
 from contextlib import ExitStack
diff --git a/tests/test_reader.py b/tests/test_reader.py
index 1d3d74d..8d6d130 100644
--- a/tests/test_reader.py
+++ b/tests/test_reader.py
@@ -1,4 +1,5 @@
 """Test reading Markdown - reader.py."""
+
 from pathlib import Path
 
 import phmutest.reader
diff --git a/tests/test_rebind.py b/tests/test_rebind.py
index e384e55..d3b0813 100644
--- a/tests/test_rebind.py
+++ b/tests/test_rebind.py
@@ -30,6 +30,7 @@
 
 To see the effect of rebind in REPL mode see test_globs.py::test_extractor().
 """
+
 import unittest
 
 import phmutest.main
diff --git a/tests/test_select.py b/tests/test_select.py
index 7633b5d..6e88646 100644
--- a/tests/test_select.py
+++ b/tests/test_select.py
@@ -1,4 +1,5 @@
 """Test test group select/deselect."""
+
 from pathlib import Path
 
 import phmutest.main
diff --git a/tests/test_session.py b/tests/test_session.py
index b17e694..2648957 100644
--- a/tests/test_session.py
+++ b/tests/test_session.py
@@ -1,4 +1,5 @@
 """Test cases for session.py."""
+
 from unittest import mock
 
 import pytest
diff --git a/tests/test_sharing.py b/tests/test_sharing.py
index 692c655..d01509b 100644
--- a/tests/test_sharing.py
+++ b/tests/test_sharing.py
@@ -1,4 +1,5 @@
 """Tests --sharing printing."""
+
 import contextlib
 import io
 import unittest
diff --git a/tests/test_subprocess.py b/tests/test_subprocess.py
index eda84df..d9e8b53 100644
--- a/tests/test_subprocess.py
+++ b/tests/test_subprocess.py
@@ -1,4 +1,5 @@
 """Test subprocess call."""
+
 import subprocess
 import sys
 
diff --git a/tests/test_tool.py b/tests/test_tool.py
index 9ed229d..1702dcd 100644
--- a/tests/test_tool.py
+++ b/tests/test_tool.py
@@ -1,4 +1,5 @@
 """Test tool.py"""
+
 import phmutest.tool
 
 
diff --git a/tests/test_wrapped_python_files.py b/tests/test_wrapped_python_files.py
index 5e7ec10..352a000 100644
--- a/tests/test_wrapped_python_files.py
+++ b/tests/test_wrapped_python_files.py
@@ -1,4 +1,5 @@
 """Check example Python file is the same as in Markdown fenced code block."""
+
 from pathlib import Path
 
 import phmutest.tool